NIH Scientists Advance Universal Flu Vaccine

July 23, 2010 | by

A universal influenza vaccine “” so-called because it could potentially provide protection from all flu strains for decades “” may become a reality because of research led by scientists from the National Institute of Allergy and Infectious Diseases (NIAID), part of the National Institutes of Health.

In experiments with mice, ferrets and monkeys, the investigators used a two-step immunization approach to elicit infection-fighting antibodies that attacked a diverse array of influenza virus strains. Current flu vaccines do not generate such broadly neutralizing antibodies, so they must be re-formulated annually to match the predominant virus strains circulating each year.

The research, led by NIAID scientist Gary J. Nabel, M.D., Ph.D., appears online ahead of print July 15 in Science Express.

“Generating broadly neutralizing antibodies to multiple strains of influenza in animals through vaccination is an important milestone in the quest for a universal influenza vaccine,” says NIAID Director Anthony S. Fauci, M.D. “This significant advance lays the groundwork for the development of a vaccine to provide long-lasting protection against any strain of influenza. A durable and effective universal influenza vaccine would have enormous ramifications for the control of influenza, a disease that claims an estimated 250,000 to 500,000 lives annually, including an average of 36,000 in the United States.”

Scientists Find New Form of Prion Disease that Damages Brain Arteries

March 9, 2010 | by

National Institutes of Health (NIH) scientists investigating how prion diseases destroy the brain have observed a new form of the disease in mice that does not cause the sponge-like brain deterioration typically seen in prion diseases. Instead, it resembles a form of human Alzheimer’s disease, cerebral amyloid angiopathy, that damages brain arteries.

NIH Newsbot Note: Cerebral amyloid angiopathy (CAA) is a neurological condition in which amyloid protein builds up on the walls of the arteries in the brain. The condition increases an individual’s risk of stroke, brain hemorrhage or dementia. There is no known effective treatment.
Cerebral amyloid angiopathy

The study results, reported by NIH scientists at the National Institute of Allergy and Infectious Diseases (NIAID), are similar to findings from two newly reported human cases of the prion disease Gerstmann-Straussler-Scheinker syndrome (GSS). This finding represents a new mechanism of prion disease brain damage, according to study author Bruce Chesebro, M.D., chief of the Laboratory of Persistent Viral Diseases at NIAID’s Rocky Mountain Laboratories.

Prion diseases, also known as transmissible spongiform encephalopathies, primarily damage the brain. Prion diseases include mad cow disease or bovine spongiform encephalopathy in cattle; scrapie in sheep; sporadic Creutzfeldt-Jakob disease (CJD), variant CJD and GSS in humans; and chronic wasting disease in deer, elk and moose.

The role of a specific cell anchor for prion protein is at the crux of the NIAID study. Normal prion protein uses a specific molecule, glycophosphoinositol (GPI), to fasten to host cells in the brain and other organs. In their study, the NIAID scientists genetically removed the GPI anchor from study mice, preventing the prion protein from fastening to cells and thereby enabling it to diffuse freely in the fluid outside the cells.

The scientists then exposed those mice to infectious scrapie and observed them for up to 500 days to see if they became sick. The researchers documented signs typical of prion disease including weight loss, lack of grooming, gait abnormalities and inactivity. But when they examined the brain tissue, they did not observe the sponge-like holes in and around nerve cells typical of prion disease. Instead, the brains contained large accumulations of prion protein plaques trapped outside blood vessels in a disease process known as cerebral amyloid angiopathy, which damages arteries, veins and capillaries in the brain. In addition, the normal pathway by which fluid drains from the brain appeared to be blocked.

Their study, Dr. Chesebro says, indicates that prion diseases can be divided into two groups:

  • those with plaques that destroy brain blood vessels
  • those without plaques that lead to the sponge-like damage to nerve cells

Dr. Chesebro says the presence or absence of the prion protein anchor appears to determine which form of disease develops.

The new mouse model used in the study and the two new human GSS cases, which also lack the usual prion protein cell anchor, are the first to show that in prion diseases, the plaque-associated damage to blood vessels can occur without the sponge-like damage to the brain. If scientists can find an inhibitor for the new form of prion disease, they might be able to use the same inhibitor to treat similar types of damage in Alzheimer’s disease, Dr. Chesebro says.

Source: NIH News

NIH Scientists Identify Maternal and Fetal Genes That Increase Preterm Birth Risk

February 4, 2010 | by

Researchers at the National Institutes of Health have identified DNA variants in mothers and fetuses that appear to increase the risk for preterm labor and delivery. The DNA variants were in genes involved in the regulation of inflammation and of the extracellular matrix, the mesh-like material that holds cells within tissues.

“A substantial body of scientific evidence indicates that inflammatory hormones may play a significant role in the labor process,” said Alan E. Guttmacher, M.D., acting director of the NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). “The current findings add evidence that individual genetic variation in that response may account for why preterm labor occurs in some pregnancies and not in others.”